WO2011101693A1

WO2011101693A1 - Driving engine (water turbine) of hydrokinetic floating power plant with enhanced efficiency degree, and hydrokinetic floating power plant module

Info

Publication number: WO2011101693A1
Application number: PCT/HR2010/000004
Authority: WO
Inventors: Ivan Korac
Original assignee: Hidra Force D.O.O
Priority date: 2010-02-22
Filing date: 2010-02-22
Publication date: 2011-08-25
Also published as: AU2010346297A1; BR112012020691A2; EP2539582A1; US20130115045A1; EA201270719A1; CN102947583A

Abstract

The invention concerned relates to improvement of hydrokinetic floating power plant (1) efficiency degree by defining of individual parameters of driving engine (13). Details and parameters of driving engine assembly (13) which contribute to enhancement of efficiency degree relate to determination of optimal gaps z and z' between blades (6) and internal planes (15) and (16) of driving engine (13) channel. Determination of optimal ratio of submerged part of blade (6) height in liquid and part of blade (6) height above liquid surface with respect to outside water line level before water flow enters confusor (10), determination of dimensions and form of confusor (10) and diffusor (11), as well as determination of distance t between blades (6) and number n simultaneously submerged blades (6) in channel (14) of driving engine (13) by which are accomplished more constant forces acting by liquid upon blades.

Description

DRIVING ENGINE (WATER TURBINE) OF HYDROKTNETIC FLOATING POWER PLANT WITH ENHANCED EFFICIENCY DEGREE, AND HYDROKINETIC

FLOATING POWER PLANT MODULE

Description of invention

The subject matter of invention is a driving engine of hydrokinetic floating power plant with enhanced efficiency degree and hydrokinetic floating power plant module for electric power generation accomplished by use of kinetic energy of free river water flow. In particular, the invention relates to determination of individual element parameters by which an increased degree of water flow efficiency in driving engine working channel as well as the efficiency of whole hydrokinetic floating power plant module is achieved.

Technical field

The invention is referred to technical field which is according to International patent classification (IPC) designated under No. FO3B9/00 and refers to driving engines for liquids driven by endless chain.

Technical Problem

All known technical solutions in the field of kinetic energy usage of hydrodynamic flow of fluids only partially take over moving fluids energy because some laws of fluids flow have been basically neglected thus no solutions have been applied in presently known assemblies which would in more significant share make use of fluid energy exploited in presently known assemblies-engines - devices.

By the present invention, technical problem to increase efficiency degree of water flow kinetic energy usage in driving engine working channel is being solved, and by this also the increase of entire floating power plant efficiency. Individual parameters of elements are specially defined, particularly such as gaps z and z' between blades and driving engine channel planes, the number n referring to number of submerged blades in driving engine channel, mutual distance between blades, part of the blade height submersed in liquid vs. part of blade height above water surface ratio, as well as dimensions of confusor and diffusor. By the present invention is solved increase of efficiency degree of hydrokinetic floating power plant module i.e. determination of optimal values above mentioned driving engine parameters, which enhance the efficiency of driving engine, thus also the module being the subject.

State of the art

All solutions up to now in the field of water kinetic energy usage lead partially, in less share, in taking over moving liquid energy because they basically neglect some fluid hydrodynamic laws and by this, no solutions have been applied with known assemblies which would to a greater extend use kinetic energy, so their efficiency is very low i.e. does not exist the commercial cost effectiveness

The document DE102007003323A1 shows a device with multiple blades submerged in water. The blades plane is perpendicular to water flow direction. The blades are connected by means of a wheel parallel to flow. Blades are fixed to transmission device which transfer longitudinal movement of blades to rotating generator shaft. Document FR2532364 refers to hydroelectric power plants using water power as source of energy where force is acting in direction of rotation of the half of blades and not perpendicular as it is with most of hydroelectric power plants. Hydroelectric power plant is located at the most suitable location at any water flowing with stream sufficient for electric power generation and without having impact to fish migration and requirements for larger intervention. The device can be completely manufactured in a factory. It includes two buoys (f) and (g) interconnected by plate (h) and contains protective grid. Between buoys are placed movable blades which are maintained perpendicular to flow direction by means of pre-stressed calibrated springs (b) and by which the force acting upon blades is controlled. Blades are fixed to two driving chains (c) and by virtue of shafts cause rotation of two kinetic wheels, gears and alternator. Document DE202006013818U1 indicates floating conveyer unit with blades driving the electric power generator. Document WO2009103131A2 indicates electric power plant producing hydroelectric power. The power plant contains a pontoon (3) with confusor (5) and diffusor (7) which are connected through working channel (6) where generators (8) are mounted within the confusor and diffusor. Along the working channel (6) and on the pontoon are placed transmission systems (4) which shafts are connected with power generator (9). Big (12) and small (13) sprockets/wheels are connected with transmission system shafts (16) of transmission system (4), which drive long (14) and short (15) sprockets elts where are long (19) and short (20) parts connected to long (14) and short (15) sprockets/belts respectively on which are placed groups of blades (18) where each individual blade (21) is at defined angle relative to working channel (6) axis. Pontoon (3) is kept at fixed location by means of anchors (2)·

No single document mentioned above solves the technical problem of increasing efficiency, but only quote hydroelectric power plant general construction characteristics without describing influence of individual characteristics on efficiency degree of water kinetic energy.

Disclosure of invention

Present invention relates to enhancement of efficiency degree of hydrokinetic floating power plant module by defining individual parameters of driving engine of hydrokinetic floating power plant. Details and parameters of driving engine elements contributing to improvement of efficiency degree of hydrokinetic power plant relate to the following:

1. determination of optimal gap between blades and internal planes of driving engine channel which is necessary, that with sufficient water and blade velocity in the channel, the wanted water level difference in front and behind blade is achieved and corresponding force on the blade is accomplished.

2. determination of optimal relation between blade height submerged in liquid and part of blade height above liquid level with respect to the external liquid level prior to inflow into confusor.

3. determination of dimensions and form of confusor and diffusor, and

4. determination of distance between blades and number of submerged blades in driving engine channel by which a more constant force of liquid acting on blades is accomplished.

Below is given a short description of drawings and detailed description of invention along with analysis of impact that have a distance between adjacent blades, gap size between blades and internal planes of driving engine channel, dimensions and form of confusor and diffusor and blade velocity. Brief description of drawings

Invention will be described in detail with reference to the drawing where:

- Fig. 1 indicates hydrokinetic floating power plant module ;

- Fig.2 indicates driving engine assembly in perspective view with sequence of interconnected blades by endless chain;

- Fig.3 indicates driving engine assembly in perspective view with sequence of interconnected blades by endless chain;

- Fig. 4 indicates driving engine assembly in perspective view with sequence of interconnected blades by endless chain;

- Fig. 5 indicates side view of driving engine assembly with sequence of interconnected blades by endless chain;

- Fig. 6 indicates schematic presentation of the driving engine in side view;

- Fig. 7 indicates schematic presentation of the driving engine in plan view;

- Fig. 8 indicates diagram of force change during tested periods for distance between blades being 0.8 m

- Fig. 9 indicates diagram of force change during tested periods for distance between blades being 3.0;

- Fig. 10 indicates diagram of force change during tested period for distance between blades being 6.0 m;

- Fig. 11 indicates diagram of force change on blades with 10% gap between tunnel and blades in tunnel model with 10 blades being at mutual distance 0.8 m;

- Fig. 12 indicates diagram of force change on blades with 20% gap between tunnel and blades in tunnel model with 10 blades being at mutual distance 0.8 m

- Fig. 13 indicates diagram of force change on blades with 30% gap between tunnel and blades in tunnel model with 10 blades being at distance 0.8 m;

- Fig 14 indicates diagram of force change on blades in tunnel model with 10 blades being at distance 0.8 m and with 10% gap between tunnel and blades at inclination of confusor 45° and diffusor 25°.

- Fig. 15 indicates diagram of force change on blades in tunnel model with 10 blades being at distance 0.8 m and 10% gap between tunnel and blades at inclination of confusor 20° and diffusor 20°; - Fig. 16 indicates diagram of correlation power P(kW) vs. velocity v (m/s) for diffusor and confusor inclination being 45° and 25° respectively.

Detail description of invention

Details and parameters of driving engine elements which contribute to improvement of driving engine efficiency degree and hydrokinetic floating power plant module are determined by implementation of commercial CDF (Computational Fluid Dynamics) software. Using commercial CDF 2-D flow of water around and within the hydrokinetic floating power plant has been simulated in order to examine the influence of geometry and position in the stream on taking over water power and parameters of driving engine (water turbine). By that so called k-ε model of turbulence and two kinds of flow have been used, particularly:

- non-stationary flow with floating blades and given velocity, and

- stationary flow with imposed given velocity at blade equal to blade velocity .

In all cases undisturbed water incoming velocity is given and equals to 2 m/s

It has been analyzed an impact to:

1) distance t between two adjacent blades being 0.8, 3.0 and 6.0 m;

2) gap size z and z' between blades (6) and planes (15) and (16) of the working channel (14) in cases when z and z' are 10, 20 and 30%;

3) inclination of confusor and diffusor plane angles α, β and γ;

4) blade velocity 1, 2 and 3 m/s for undisturbed flow velocity being 2 m/s;

5) confusor and diffusor input and output surface ratio respectively, and working channel cross -section surface ratio being 3:1 and 4:1.

Hydrokinetic floating power plant module is presented in Fig.1. Hydrokinetic floating power plant module (1) is anchored at determined location by means of four concrete blocks (3) which are connected through four buoys (2) to floating power plant platform. Hydrokinetic floating power plant module driving engine (13) is accommodated within casing (4). Fig. 2 to 4 present perspective view of driving engine assembly (13) with sequence of blades (6) interconnected by endless chain (7). Fig. 5 indicates side view of driving engine assembly with sequence of blades (6) interconnected by endless chain (7). In the driving engine (13) kinetic energy of water, by the quantity of movement change, is converted into mechanical rotary energy. The working wheel shaft is connected by means of gear assemblies with generator (9) where mechanical rotary energy is converted in electrical energy. In the working channel (14) of driving engine (13) is installed sequence of blades (6), where the blade plane is perpendicular to water flow direction. In order to achieve continuous movement of blades (6), they are interconnected by endless chain (7). On the front and back side of driving engine (13) are fitted gear assemblies/working wheels which linear movement of blades (6) in the cannel (14) convert into rotary movement, maintain continuous movement of blades (6) and direct the blade (6) entering into water and coming out perpendicular related to water flow in the working channel (14) of driving engine (13). Directed - vertical entry and exit of blades (6) in and out from water enable to take over water flow energy evenly without negative effects. To achieve water force acting upon blades (6) as much as possible steadily, the ratio of non-submerged and submerged parts of blade height in relation to the outside water line before inflow into confusor amounts 10 to 20%. Furthermore, in order to accomplish as much as possible stable water force acting upon blades (6), the range of number n simultaneously entirely submerged blades (6) in the channel (14) of driving engine (13) equals 2-6. Gears/working wheels assemblies at front and back side of driving engine (13) convert linear movement of blades (6) in working channel (14) into rotary movement, and kinetic energy taken over by front wheel shaft is converted into mechanical energy carried over to generator rotor (9) which generates electrical energy.

Working channel (14) of driving engine (13) is formed by two internal side planes (15) and bottom plane (16). Confusor (10) is located at the entry of working channel (14) by which river flow is collected and directed into working channel (14) of driving engine (13). Dimensions and form of confusor enables collection of targeted quantity of water out from river flow and increase water velocity in driving engine channel when compared to the water level in the free river flow. For this purpose, the cross section surface of input confusor A_<, is three times bigger than cross-section surface A of the driving engine cannel (the ratio of confusor surface with respect to channel surface A₀ / A = 3/1). Confusor (10) is bounded by three planes, i.e. by two side planes (17) and bottom plane (18). Fig. 6 & 7 show angles a i γ under which confusor planes (17) and (18) are connected to working channel. Working channel (14) is bounded by three planes set under 90° angle. Side planes (17) of confusor (10) are set under angle a with respect to the plane of internal side planes (15), while confusor bottom plane (18) is set under angle γ with respect to bottom plane (16) of the working channel (14) (see Figs. 5 & 6). Inclination angle a of side planes (17) and angle γ of confusor (10) lower plane (18) enable collection i.e. overtake 40% bigger quantity of directed water flow into working channel (14), which would otherwise, without above mentioned inclinations, in case when α = γ = 0, due to hydrodynamics laws, provoke effect of passing this quantity of water under driving engine working channel. Fig. 5 indicates rise of overtaken water flow (level of internal water) with respect to the water flow level before entering into confusor (10) ( the level of outside water).

At the outlet from driving engine working channel (14) is located diffusor (11) which promotes accelerated water output from channel (14) and by this rapidly equalizes increased height of water column in the channel with height of water in the free flow. By this effect of hydraulic jump is additionally enforced at the last blade (6) in the cannel (14), which from the linear movement goes into circular movement, and goes out perpendicularly to water flow direction in the channel. Diffusor (11) is also bounded by three planes, i.e. by two side planes (19) and bottom plane (20). Side plane (19) of diffusor (11) is set under angle β with respect to the plane of internal side planes (15) of the working channel (14). Fig. 6&7 illustrate schematic presentation of the driving engine in side view and top view showing values /, h, t, z and z' where / means width of the working channel (14), h the height of water level in the working channel (14), t is distance between adjacent blades (6), z and z' is gap between internal planes (15) & (16) of the working channel (14) and end edges of blades (6). The gap z is expressed in %, and is defined as ratio between channel width / and the part being between end edge of the blades (6) and planes (15) of the working channel (14). The gap z' is expressed in %, and is defined as ratio between the height of water level h and the part being between end edge of the blades (6) and bottom plane (16) of the working channel (14).

The impact of confusor and diffusor inclination has been examined on the tunnel model with 10 blades having distance between them 0,8 m and gaps z and z' 10%.

The following cases have been tested:

- confusor angle 2a = 45°, diffusor angle 2β = 25° - 200 cycles

- confusor angle 2a = 20° diffusor angle 2β = 20° - 200 cycles

From analysis of diagrams presented in Fig.14 and 15 can be seen that with smaller confusor and diffusor angle (20°), see Fig.15, almost twice smaller fore is accomplished than it would be the case with bigger confusor and diffusor angles (45° and 25°), see. Fig.14. Increased efficiency degree of the driving engine (13) is achieved:

- for confusor side planes (17) inclination with respect to the plane of working channel side planes (15), angle a in range from 20° to 30°,

- for confusor bottom plane (18) inclination with respect to the working channel bottom plane (16) , angle γ in range from 10° to 30°, and - for diffusor side planes (19) inclination with respect to the plane of working channel side planes (15), angle β in range from 10° to 20°.

Apart from influence of plane inclinations α, γ and β of confusor (10) and diffusor (11) to the efficiency degree of driving engine (13), it has been analyzed influence of ratio confusor inlet cross section AO and diffusor outlet cross section B0 and cross section A of the working channel (14). It has been examined a variant with confusor and diffusor having four times larger cross section AO and B0 respectively than cross section A of the working channel (14) for various blade velocities. These results are given in the table below where Y denotes distance from adjacent module, v_lop is blade velocity and v;_n is velocity of water flow.

The greatest power has been obtained in the case of 5.5 m distance from the adjacent block, with confusor inlet cross section AO and diffusor outlet cross section B0 increase four times with respect to the working channel (14) cross section A, at blade velocity v_lop=2.66 m/s and water velocity Vj_n = 2 m/s. This case is presented in the table in bold. The ratio of confusor input cross section AO and working channel cross section A - AO/ A, and ratio of diffusor outlet cross section B0 and working channel cross section A - B0/A , are within range 2 to 4.

Fig. 6&7 illustrate schematic presentation of driving engine in side view with values /, h, t, z, and z' where / is width of working channel (14), h is height of water level in working channel (14), t is distance between adjacent blades (6) and z and z' are gaps between internal planes (15) and (16) of working channel (14) and end edges of blades (6). Increased water velocity and level in working channel, gaps z and z' between planes (15) and (16) of working channel (14) and end edges of blades (6) as well as decreased blade velocity in time of overtake of water kinetic energy result in water column height difference before and after the blade by which the effect of hydraulic jump occurs resulting with increase of force upon the blade, i.e. increase in take over power at blade. In the example of a tunnel with 10 blades, with distance between them being 0.8 m, the influence of gap size z and z' to the accomplished forces on all blades (6) have been examined. Fig. 11, 12 and 13 present diagrams of force changes on the blades with gaps z and z' between working channel (14) and end edges of blades (6) being 10%, 20% and 30%. The following cases have been examined:

- gap z and z' 10% - 200 cycles

- gap z and z' 20% - 400 cycles

- gap z and z' 30% - 400 cycles

From diagrams in Fig. 11, 12 and 13 one can see that greater forces have been realized with lower gap values z and z'. Out of examined cases, the greatest force has been realized in case of 10% gap between tunnel and end edges of blade (6). Accordingly, the gaps z and z' by which have been realized greater forces are in the range from 2% to 10%» of the total blade (6) surface.

Further on, the influence of distance t between two adjacent blades has been analyzed. It was analyzed the working channel (14) with one blade traveling down the stream at given velocity and after certain time the blade suddenly raised while at the beginning of tunnel in the same time occurred another blade. The following cases have been examined:

- distance t between blades 0.8 m - 600 cycles

- distance t between blades 3.0 m - 200 cycles

- distance t between blades 6.0 m - 200 cycles

Diagrams on Fig. 8, 9 and 10 present change of force during testing cycles, where one cycle is travel time for one blade from its occurrence at the tunnel inlet until its rising, for distance between blades 0.8m, 3.0m and 6.0 m.

It was needed 200 to 600 cycles to stabilize periodic flow.

From diagrams in Fig. 8, 9 and 10 can be seen how distance between blades affects the force magnitude. With the distance being 8.8 m the realized force is between 40 and 50 kN, and it is unstable. Unlike to previous case, with distance being 3 to 6 m the realized force was about 58 kN and was stable within the whole range. Though, with distance between blades being 6 m the realized force was a little bit bigger, however from commercial stand point such dimensions are not acceptable. Increased efficiency degree of the driving engine (13) is accomplished for distance t between blades in range from 0.5-3.0 m.

By analysis of the influence of blade velocity in example with stationary flow, the exchanged energy between tunnel inlet and outlet cross sections has been calculated. The water velocity at the inlet in domain was 2m/s, and confusor (10) and diffusor (11) angles were 2α=45° and 2β=25°. Fig. 16 indicates diagram of power P (kW) dependence on velocity v (m/s) for diffusor (11) angles: 2 =45° and 2β=25°. Examined were cases for:

- blade velocity 1 m/s

- blade velocity 2 m/s

- blade velocity 3 m/s

Analysis of power exchanged shows that the greatest power is achieved with blade velocity being 2 m/s, which corresponds to optimal velocity of 33% of undisturbed velocity through tunnel (without blades), and which would be 6 m/s with three times larger tunnel cross section, and what is showing a simple mathematical analysis of takeover power optimization in dependence of blade velocity and at given stream velocity.

Finally, for solution of technical problem how to increase water flow kinetic energy efficiency degree in the working channel (14) of driving engine assembly (13), and by this to increase efficiency of the whole hydrokinetic floating power plant (1), ranges of parameters of individual elements are the following:

gap between blades and working channel

z i z* 2 - 10 %

distance between blades

t 0,5 - 3,0 m

confusor angle

a . 20°- 30°

diffusor angle

β 10° - 20°

reduction of confusor

AO/A 2 - 4

widening of diffusor

number of blades in working channel

n 2 - 6

confusor angle with respect to horizontal line

v 10° - 30° Description of implementation

Hydrokinetic floating power plant (1) can be used together with driving engine assembly (13) as integrated floating module which can be individually or aggregately installed by anchoring in free river streams and derivative canals. In this way electric power is generated for end user by ecological acceptable source which contributes to generation of electric power from renewable sources. By this, so generated electric power contributes to general energetic efficiency and reduction of greenhouse gases. This type of floating module enables flora and fauna migration from river habitation, and because all assemblies are of mechanical type, there is no environment pollution.

Claims

1. Driving engine (13) of hydrokinetic floating power plant (1) with enhanced efficiency degree consists of working channel (14), bounded by internal planes (15) and (16) with cross section surface A, within which is located an sequence of blades (6) interconnected by two parallel endless chains (7), where adjacent blades (6) are placed at mutual distance t; confusor (10) is located at inlet of working channel (14) and is having inlet cross section surface AO by which river flow is collected and directed into working channel (14) of driving engine (13); and diffusor (11) set at outlet of working channel (14) of driving engine (13) having outlet cross section surface BO, where above mentioned driving engine (13) at its front and back ends has gear assemblies, which convert linear movement of blades (6) in working channel (14) to rotary movement, and overtaken kinetic energy is converted by means of gear shafts to mechanical power carried over to generator rotor (9) which generates electric power; where mentioned gear assemblies maintain continuous blades (6) movement and set blades (6) at inlet and outlet perpendicular to water flow direction in working channel (14) of driving engine (13), where z and z' are gaps between internal working channel (14) planes (15) and (16) and end edges of blades (6), characterized by that inclination angle a of side planes (17) and confusor (10) with respect to side surfaces plane (15) of working channel (14), is in range from 20° to 30°; inclination angle γ of confusor (10) bottom plane (18) with respect to working channel (14) bottom plane (16) is in range from 10° to 30°; and inclination angle β of diffusor (11) side surfaces (19) with respect to working channel (14) side surfaces (15) plane, is in range from 10° to 20°.

2. Driving engine (13) according to claim 1, characterized by that ratio AO/ A, confusor (10) inlet cross section AO and working channel (14) cross section A , is 2 to 4.

3. Driving engine (13) according to claim 2, characterized by that ratio AO/A, of confusor (10) inlet cross section surface AO and working channel (14) cross section A, is 4.

4. Driving engine (13) according to claim 1, characterized by that ratio of diffusor (11) outlet cross section surface B0 and working channel (14) cross section A is 2 to 4.

5. Driving engine (13) according to claim 4, characterized by that ratio of diffusor (11) outlet cross section surface B0 and working channel (14) cross section A is 4.

6. Driving engine (13) according to claim 1, characterized by that ratio of un- submerged part of blade (6) height and submerged part of blade (6) height with respect to outside water line prior to water inflow into confusor (10) is 10 to 25%.

7. The driving engine (13) according to claim 1, characterized by that number n of simultaneously entirely submerged blades (6) in channel (14) of driving engine (13) is within range 2-6.

8. Driving engine (13) according to claim 1, characterized by that size of gaps z and z' is within range 2-10%.

9. Driving engine (13) according to claim 8, characterized by that size of gaps z and z' is 10%.

10. Driving engine (13) according to claim 1, characterized by that range of distance t between adjacent blades (6) is 0.5 - 3.0 m

11. Driving engine (13) according to claim 10, characterized by that distance between adjacent blades (6) is 3.0 m.

12. Hydrokinetic floating power plant module (1) with enhanced efficiency degree is anchored at defined place by means of four concrete blocks (3) which are by virtue of four buoys (2) connected to the floating power plant platform, consisting of driving engine (13) placed within casing (4), where the above mentioned driving engine (13) is bound by internal planes (15) and (16), having cross section surface A, within which is placed an sequence of blades (6) mutually interconnected by two parallel endless chains (7) where adjacent blades (6) are set at distance t; confusor (10) accommodated at inlet of working channel (14) having input cross section surface AO by which river flow is collected and directed into working channel (14) of driving engine (13); and diffusor (11) accommodated at the outlet of working channel (14) of driving engine (13) having outlet cross section surface B0 where above mentioned driving engine (13) at its front and back ends contains gear assemblies which convert linear movement of blades (6) in working channel (14) to rotary movement and overtaken kinetic energy by means of gear assembly shafts transfers to generator rotor (9) generating electric power; where above mentioned gear assemblies maintain continuous movement of blades (6) and direct input and output of blades (6) into water perpendicular to water flow direction in working channel (14) of driving engine (13), where between internal planes (15) and )16) of working channel (14) and blade ends (6) are gaps z and z characterized by that inclination angle a of confusor (10) side planes (17) with respect to the working channel (14) side planes (15), is in range from 20° to 30°; inclination angle γ of bottom plane (18) of confusor (10) with respect to bottom plane (16) of working channel (14) is in the range from 10° to 30 °; and that inclination angle β of diffusor (11) side planes (19) with respect to working channel (14) side planes (15) is in the range from 10° to 20°.

13. Module (1) according to claim 12, characterized by that the ratio AO/A ,of inlet cross section surface A_o0 of confusor (10) and cross section surface A of working channel (14), is 2 to 4.

14. Module (1) according to claim 13, characterized by that the ratio AO/ A, of inlet cross section surface AO of confusor (10) and cross section surface A of working channel (14), is 4.

15. Module (1) according to claim (12), characterized by that ratio B0/A of diffusor (11) outlet cross section surface and working channel (14) cross section surface A is 2 to 4.

16. Module (1) according to claim 12 characterized by that ratio B0/A of diffusor (11) outlet cross section surface B0 and working channel (14) cross section surface A is 4.

17. Module (1) according to claim 12, characterized by that ratio of un-submerged part of blade (6) height with respect to outside water line level prior to water inflow into confusor (10) is 10 to 25%.

18. Module (1) according to claim 12, characterized by that number n of simultaneously submerged blades (6) in channel (14) of driving engine (13) is in range 2 - 6.

19. Module (1) according to claim 12, characterized by that gap size z and z' is in the range from 2-10%.

20. Module (1) according to claim 19, characterized by that gap size z and z' is 10%.

21. Module (1) according to claim 12, characterized by that the range of distance t between adjacent blades (6) is 0.5 - 3.0 m.

22. Module (1) according to claim 21, characterized by that distance t between adjacent blades (6) is 3.0 m.